Thursday, May 25, 2017

Re: Splitter not showing in SplitLayoutPanel

"Layout panels" (RequiresResize) need to be sized "from the outside" (they don't have an "intrinsic size" depending on their content), and this means you either need to give them an explicit, absolute size (i.e. no percentages or other relative units) or have an uninterruptible chain of parent layout panels (RequiresResize/ProvidesResize, or IIRC possibly HeaderPanel's content widget) up until one has and an explicit, absolute size, or can give one to its content (RootLayoutPanel or ResizeLayoutPanel)

Your FlowPanels and Composites break that chain. Maybe try using LayoutPanel/DockLayoutPanel instead (and ResizeComposite).

But understand that this is a fundamental shift in how the UI is built and behaves (e.g. no scrolling, unless you use ScrollPanels; and no "intrinsic sizing"). Layout panels are much more "app-y" than "webby".

On Thursday, May 25, 2017 at 3:27:33 PM UTC+2, Harry Wagner wrote:
I have inherited a GWT application that was written back in GWT's 1.x days. It has since been migrated to 2.4 but will only run in quirks mode. I am tasked with migrating it to 2.8 and making it run in standards mode. It is a challenge for me. I have years of Java experience but no GWT experience. The app relies heavily on HorizontalPanel and VerticalPanel which I am changing to FlowPanel. The app also uses VerticalSplitPanel which I am trying to replace with SplitLayoutPanel but can't get the splitters to show, even when this LOC "Window.alert("SplitterSize: " + rightPanel.getSplitterSize());" indicates 10px, which is what I am expecting. I have struggled with this and am wondering if I might be trying to do something not in SplitLayoutPanel's nature? Here is what my panel layout looks like (I am not using UIBinder). Hopefully downstream formatting won't make a mess of the layout.

Should this work, or am I doing something with SplitLayoutPanel that it was not designed for? TIA!


Root Panel (RootLayoutPanel)
     RootWidget (extends FlowPanel)
          Top Panel (FlowPanel)
          hpPanel (FlowPanel)
               cmdPanel (Composite)
                    rpPanel (SplitLayoutPanel)
                          listPanel (extends FlexTable)
                          detailPanel (extends Composite)
                    iconPanel (extends FlowPanel)

             top panel                      |
cmdPanel |.    listPanel.            |
                 |                                |
                 |                                |
                 |----- splitter here ----|
                 |                                |                                                
                 |     detailPanel.        |
                 |                                |
                 |----- splitter here ----|
                 |                                |
                 |      iconPanel.         |
                 |                                |

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